Preheat oven to 425 F. Grease cookie sheet and set aside. Combine flour, cornmeal, baking powder and salt in a food processor and run for about 10 seconds, ensuring even distribution. Add banana and allow to run until flour is pebble-like. Transfer to a mixing bowl and combine with non-dairy milk and maple, stirring until well combined. Use a spoon to drop 6 biscuits at least 2" apart. Bake about 7-8 minutes, until edges are just crisp and slightly brown.